JPH11293093A - Epoxy resin composition for printed-wiring board, its preparation and prepreg and metal-clad laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition for printed-wiring boards which can improve dispersion of a white pigment in a resin and increase optical reflectance by blending an epoxy resin compound, titanium oxide and a specific silane compound. SOLUTION: This epoxy resin composition contains an epoxy resin compound, titanium oxide and a silane compound of the formula: X-Si(OR)n . (wherein n is 2 or 3; X is a functional group which reacts with the epoxy resin; and X is a 1-3C alkyl group). The epoxy resin compound contains an epoxy resin and a curing agent. The X in the formula includes, for example, an amino group, an epoxy group, a mercapto group and the like and an epoxy group is the most preferred. A content of the silane compound of the formula is preferably 0.5-5.0 wt.% based on titanium oxide. A content of titanium oxide is preferably 10-50 wt.% based on the epoxy resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition for a printed wiring board used for electronic equipment and the like, a method for producing the same, and a prepreg and a metal foil-clad laminate.

[0002]

2. Description of the Related Art In recent years, light emitting diodes (LEDs) have become mainstream as light emitters used in electronic equipment and the like. In mobile phones and car stereos, a chip LE in which LED elements are arranged on a printed wiring board and sealed with a transparent resin
D is used. In a chip LED, it is necessary to increase the light reflectance of a printed wiring board on the back surface of the LED element in order to efficiently emit light to the upper surface of the LED element.

In order to improve the light reflectance of a printed wiring board, it has been attempted to add a white pigment such as titanium oxide to a base resin such as an epoxy resin for forming the printed wiring board. However, sufficient results were not obtained due to poor dispersibility of the white pigment.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above points, and is an epoxy resin for a printed wiring board capable of improving the light reflectance by improving the dispersion of a white pigment in a resin. It is an object of the present invention to provide a composition, a method for producing the same, and a prepreg and a laminate produced using the epoxy resin composition.

[0005]

The epoxy resin composition according to the first aspect of the present invention comprises an epoxy resin compound, titanium oxide, and a silane compound represented by the following formula (1). It is assumed that.

X-Si (OR) n (1) where n is 2 or 3, X is a functional group that reacts with the epoxy resin, and R is a C1-C3 alkyl group.

The epoxy resin composition according to the invention of claim 2 of the present application is characterized in that, in addition to the features of the epoxy resin composition described in claim 1, the content of titanium oxide is less than that of the epoxy resin.
It is characterized by being 10% by weight to 50% by weight.

[0008] The epoxy resin composition according to the third aspect of the present invention is characterized in that, in addition to the features of the epoxy resin composition according to the first or second aspect, the content of the silane compound of the formula (1) is less than that of titanium oxide. 0.5% by weight to 5.0% by weight with respect to

The epoxy resin composition according to the invention of claim 4 of the present application has the features of the epoxy resin composition according to any one of claims 1 to 3, and in addition, X in the formula (1) is an epoxy group. It is characterized by comprising a silane compound.

The method for producing an epoxy resin according to the present invention comprises:
It is characterized by adding titanium oxide after adding a silane compound of the formula (1) to an epoxy resin compound.

[0011] A prepreg according to the present invention is obtained by impregnating a substrate with a solution of the epoxy resin composition according to any one of claims 1 to 4 in a solvent and drying. is there.

[0012] A metal foil-clad laminate according to the present invention is characterized in that a metal foil is stacked on a prepreg according to claim 6 and is formed by heating and pressing.

[0013]

Embodiments of the present invention will be described below.

The epoxy resin composition according to the present invention comprises an epoxy resin compound, titanium oxide, and a silane compound represented by the following formula (1).

X-Si (OR) n (1) where n is 2 or 3, X is a functional group which reacts with the epoxy resin, and R is a C1-C3 alkyl group.

The epoxy resin compound used in the present invention contains an epoxy resin and a curing agent.

The epoxy resin contained in the epoxy resin compound of the present invention is an epoxy resin having an average of two or more epoxy groups in one molecule.
Epoxy resin, bisphenol F epoxy resin, phenol novolak epoxy resin, bisphenol A
Novolak type epoxy resin, cresol novolak type epoxy resin, diaminodiphenyl type epoxy resin, trifunctional type epoxy resin, and those obtained by modifying a hydrogen atom in these epoxy resins with a halogen atom can be exemplified. Alternatively, two or more kinds can be used in combination.

The curing agent contained in the epoxy resin compound of the present invention is not particularly limited, but includes amide curing agents (dicyandiamide, aliphatic polyamine, etc.), aliphatic amine curing agents (triethylamine, diethylamine, etc.),
Aromatic amine curing agents (diaminodiphenylmethane, metaphenylenediamine, etc.), phenolic curing agents (phenol novolak resin, cresol novolak resin, etc.), imidazole curing agents (2-ethyl-4-methylimidazole, 2-phenylimidazole) And a curing agent such as an acid anhydride-based curing agent (methylhexahydrophthalic anhydride). These curing agents can be used alone or in combination of two or more.

The epoxy resin compound used in the present invention may optionally contain a curing catalyst or other additives.

The curing catalyst optionally contained in the epoxy resin compound of the present invention is not particularly limited, but includes imidazoles (eg, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole), Secondary amines (1,8-diaza-bicyclo [5.4.0] undecene, triethylenediamine, benzyldimethylamine, etc.), organic phosphines (tributylphosphine, triphenylphosphine, etc.), tetraphenylboron salts (tetraphenylphosphonium tetraphenyl) And the like, and these curing catalysts can be used alone or in combination of two or more. The content of these curing catalysts is preferably 1 part by weight or less based on 100 parts by weight of the solid content of the epoxy resin composition.

Examples of additives optionally contained in the epoxy resin compound of the present invention include thermoplastic resins (polyphenylene oxide, polyimide, etc.), rubbers (carboxyl-terminated nitrile-butadiene rubber, core-shell rubber, etc.), and the like. Modified thermoplastic resins and rubbers can be exemplified, and these additives can be used alone or in combination of two or more. The content of titanium oxide in the epoxy resin composition of the present invention is 10% by weight to 50% by weight with respect to the epoxy resin, in other words, the content of titanium oxide is 10 parts by weight with respect to 100 parts by weight of the epoxy resin. Preferably it is 50 parts by weight. If the content of titanium oxide is less than 10 parts by weight with respect to 100 parts by weight of the epoxy resin, the light reflectance does not increase because sufficient white color is not obtained in the epoxy resin composition. When the amount exceeds 50 parts by weight with respect to the parts by weight, the strength of the laminate prepared using the epoxy resin composition is reduced.
The titanium oxide used in the present invention is not particularly limited, but preferably has an average particle diameter of 0.5 μm or less.

The silane compound used in the present invention is a compound represented by the following formula (1), X-Si (OR) n (1) where n is 2 or 3, and X reacts with the epoxy resin. Although it is a functional group, an amino group, an epoxy group, or a mercapto group can be exemplified, and an epoxy group is most preferable. Epoxy groups, of course, have extremely good compatibility with epoxy resins,
This is because the dispersibility is also the most excellent. R is C1-C
3 alkyl groups. The content of the silane compound used in the present invention is 0.5% by weight to 5.0% by weight based on titanium oxide, in other words, the content of the silane compound is titanium oxide.
It is preferred that the amount be 0.5 to 5.0 parts by weight based on 100 parts by weight. If the content of the silane compound is less than 0.5 part by weight with respect to 100 parts by weight of titanium oxide, the dispersibility of the titanium oxide is reduced, sufficient light reflectance is not obtained, and the content of the silane compound is 100 parts by weight of titanium oxide. If the amount exceeds 5.0 parts by weight, the heat resistance of the obtained laminate may decrease.

In producing the epoxy resin composition of the present invention, it is preferable to first add a silane compound to the epoxy resin compound and stir, then add titanium oxide and stir. This is because if the silane compound is dispersed in the epoxy resin compound in advance, the titanium oxide added later is less likely to undergo secondary aggregation. As a result, the epoxy resin composition prepared by this method has good dispersion of titanium oxide and is efficiently white, so that the light reflectance is improved.

The varnish-like epoxy resin composition is impregnated into a substrate and dried by heating to prepare a prepreg. The substrate is not particularly limited, but may be glass fiber,
Cloth or nonwoven fabric using fibers such as aramid fiber, polyester fiber, and nylon fiber, and papers such as kraft paper and linter paper can be exemplified.
Among these, inorganic fibers such as glass cloth are excellent in heat resistance and moisture resistance, and are preferable as the base material.

The amount of resin in the prepreg is 10
It is preferably 40 to 80 parts by weight based on 0 parts by weight. If the amount is less than 40 parts by weight, air bubbles may remain in the laminated plate formed using the prepreg, or a defective thickness may occur. When the amount exceeds 80 parts by weight, there is a possibility that a sheet thickness defect occurs.

A predetermined number of the obtained prepregs and a metal foil are stacked and heated and pressed to produce a laminate. Examples of the metal foil include a copper foil and an aluminum foil.

【Example】

Hereinafter, the present invention will be described specifically with reference to examples. In this example, parts by weight are simply referred to as "parts". (Example 1) Epoxy resin A has an epoxy equivalent of 500
Is a tetrabromobisphenol A type epoxy resin (manufactured by Dow Chemical, trade name DER511). Also,
As the epoxy resin B, a cresol novolak type epoxy resin having an epoxy equivalent of 200 (trade name: YD
CN702) was prepared.

85.5 parts of epoxy resin A, 12 parts of epoxy resin B, 2.5 parts of curing agent dicyanamide, and 0.1 part of curing catalyst 2-ethyl-4-methylimidazole (manufactured by Shikoku Chemicals)
Was added to 70 parts of dimethylformamide (DMF), and 25 parts of titanium oxide (trade name, manufactured by Tomem Products, Inc.)
After adding and stirring TCR-73), the silane compound B (Shin-Etsu Chemical Co., Ltd.)
3 parts of brand name KBM603) were added and stirred to obtain an epoxy resin composition.

The obtained varnish-like epoxy resin composition was impregnated into a glass cloth (manufactured by Asahi Sheebel, trade name: 216L), and then dried at 150 ° C. to a thickness of 0.1 mm and a resin content of about 50% by weight. I got a prepreg.

Eight prepregs described above are laminated, and a copper foil (35 μm) placed on both outer sides thereof is sandwiched between metal plates.
The laminate was obtained by heating and pressing. Molding conditions are maximum temperature
170 ° C., pressure 3.9 MPa, time 90 minutes. (Example 2) 100 parts of polyphenylene oxide having a number average molecular weight of 20,000 (manufactured by Nippon GE Plastics, product number 640-111),
Bisphenol (10 parts) and benzoyl peroxide (10 parts) were added to toluene (100 parts) and reacted at 90 ° C. for 60 minutes with stirring to obtain a liquid modified phenol.

59.5 parts of the epoxy resin A, 40 parts of the above modified phenol, 0.5 part of the curing agent diaminodiphenylmethane, and 0.5 part of the curing catalyst 2-ethyl-4-methylimidazole were added to 70 parts of toluene. Part of titanium oxide (trade name: TCR-73, manufactured by Tomme Products) and stirred, and then silane compound A (trade name: KBM40, manufactured by Shin-Etsu Chemical Co., Ltd.) which is a trimethoxysilane having an epoxy group
3) was added and stirred to obtain an epoxy resin composition.

Using the varnish-like epoxy resin composition, a prepreg was obtained in the same manner as in Example 1.

Eight of the above prepregs are laminated, and a copper foil (35 μm) placed on both outer sides thereof is sandwiched between metal plates.
The laminate was obtained by heating and pressing. Molding conditions are maximum temperature
The temperature was 200 ° C., the pressure was 3.9 MPa, and the time was 120 minutes. (Example 3) 54 parts of an epoxy resin A, 23 parts of an epoxy resin B, 23 parts of a phenol novolak resin having a phenolic hydroxyl equivalent of 105 as a curing agent (trade name: Tamanol 752, manufactured by Arakawa Chemical Industries), and 0.1 part Curing catalyst for 2-ethyl-4-
Methylimidazole (manufactured by Shikoku Kasei) was added to 70 parts of methyl ethyl ketone (MEK), and 25 parts of titanium oxide (manufactured by Tomem Products, trade name: TCR-73) was added. After stirring, trimethoxy having an amino group was added. 3 parts of a silane compound B as a silane were added and stirred to obtain an epoxy resin composition. Hereinafter, a prepreg was prepared in the same manner as in Example 1 to obtain a laminate. (Example 4) A laminate was obtained in the same manner as in Example 2 except that 3 parts of silane compound B was used instead of 3 parts of silane compound A. (Example 5) A laminate was obtained in the same manner as in Example 2, except that titanium oxide was added in an increased amount to 45 parts instead of 25 parts. (Example 6) A laminate was obtained in the same manner as in Example 2 except that titanium oxide was added in a reduced amount of 15 parts instead of 25 parts. (Example 7) A laminated board was obtained in the same manner as in Example 2 except that titanium oxide was added after the silane compound A was added. (Example 8) A laminated board was obtained in the same manner as in Example 2, except that the silane compound A was added in a reduced amount of 1 part instead of 3 parts. (Example 9) A laminated board was obtained in the same manner as in Example 2, except that silane compound A was added in an increased amount of 4 parts instead of 3 parts. Comparative Example A laminate was obtained in the same manner as in Example 2 except that no silane compound was added.

[0034]

【table 1】 (Evaluation method) Interlaminar peel strength (adhesion strength between prepregs forming a laminate) The obtained laminate was cut into strips with a width of 10 mm, and one prepreg on the surface of the laminate was cut perpendicular to the laminate. The strength when peeled off at 50 mm / min in the direction was measured.

Heat resistance The obtained laminate was cut into a square of 50 mm, left in an oven at 240 ° C. for 1 hour, and the peeling of the copper foil was visually evaluated. The case where peeling did not occur was evaluated as 、, and the case where peeling occurred was evaluated as x.

Light Reflectivity The obtained laminate was etched to expose the surface of the prepreg, and the light reflectance of that portion was measured using a spectrophotometer. The light wavelength was 680 nm. (result)

As shown in Table 1, it was confirmed that the laminate obtained in each of the examples had better light reflectance than the laminate obtained in the comparative example.

[0038]

As described above, the epoxy resin composition according to claim 1 of the present invention comprises an epoxy resin compound, titanium oxide, and the following formula (1): X-Si (OR) n (1) Wherein n is 2 or 3, X is a functional group that reacts with the epoxy resin, and R is a C1-C3 alkyl group.)
Since it contains a silane compound represented by, the dispersibility of titanium oxide is improved, and a prepreg is prepared using the present epoxy resin composition, and when a laminate is further molded, one having excellent light reflectance is obtained. can get.

The epoxy resin composition according to the second aspect has a titanium oxide content of 10 to the epoxy resin.
Since the content is from 50% by weight to 50% by weight, a laminate having excellent light reflectance and strength can be obtained by adding an optimum amount of titanium oxide as a pigment.

In the epoxy resin composition according to the present invention, the content of the silane compound of the formula (1) is 0.5% by weight to 5.0% by weight with respect to titanium oxide. By adding the compound in an optimum amount, the dispersion of the titanium oxide becomes good, and a laminate having excellent light reflectance and heat resistance can be obtained.

In the epoxy resin composition according to the present invention, since a silane compound in which X in the formula (1) is an epoxy group is contained, a silane compound having high compatibility with the epoxy resin is used. Thus, the dispersion of titanium oxide becomes good, and a laminate having excellent light reflectance can be obtained.

In the method for producing the epoxy resin composition of the present invention, the silane compound of the formula (1) is added to the epoxy resin compound, and then the titanium oxide is added. As a result, the dispersion of the titanium oxide becomes good, and a laminate having excellent light reflectance can be obtained.

The prepreg of the present invention may be used on a base material according to claim 1.
The epoxy resin composition described in any of 1 to 4 above is impregnated with a solution obtained by dissolving the epoxy resin composition in a solvent and dried to prepare a laminate having excellent light reflectivity.

In the laminate of the present invention, a metal foil is superimposed on the above-mentioned prepreg and molded by heating and pressing, so that an excellent light reflectance can be obtained.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H05K 1/03 610 H05K 1/03 610L

Claims (7)

[Claims] 1. An epoxy resin composition comprising an epoxy resin compound, titanium oxide, and a silane compound represented by the following formula (1). X-Si (OR) n (1) (where n is 2 or 3, X is a functional group that reacts with the epoxy resin, and R is a C1-C3 alkyl group.) 2. The epoxy resin composition according to claim 1, wherein the content of titanium oxide is 10% by weight to 50% by weight based on the epoxy resin. 3. The content of the silane compound of the formula (1) is:
The epoxy resin composition according to claim 1, wherein the content is 0.5% by weight to 5.0% by weight based on titanium oxide. 4. The epoxy resin composition according to claim 1, wherein a silane compound in which X in the formula (1) is an epoxy group is contained. 5. The epoxy resin composition according to claim 1, wherein a titanium oxide is added to the epoxy resin compound after adding a silane compound of the formula (1). Production method. 6. A prepreg obtained by impregnating a base material with the epoxy resin composition according to any one of claims 1 to 4 dissolved in a solvent, followed by drying. 7. A metal foil-clad laminate formed by laminating a metal foil on the prepreg according to claim 6, and heating and pressing the metal foil.